System for the transmission of electrical energy.



c". n. LANNING. SYSTEM FOR THE TRANSMISSION OF ELECTRICAL ENBRGY.

APPLICATION FILED JUNE 2, 1911 Patented Feb. 11, 1913.

%Inventvrf N b [4? a l 7 znfy/ witness-es.

fiouxz I {I Is SYSTEM FOR THE TRANSMISSION OEELEGTRICAL ENERGY.

I Specification ot Letters Patent.

Patented Feb. 11, 1913.

Original application filed December 26, 1905, Serial No. 293,216. Divided and this application filed'J'une 2,

1911. Serial No. 630,811.

To all whom it may concern:

Be it known that I, CHARLES D. LANNING, a citizen of the United States, and a resident of Boston, county of Suffolk, State of Massachusetts, (Whose post-office address is 95 "Milk street, Boston, Massachusetts) have invented an Improvement in Systems tor the Transmission of Electrical Energy, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the draw:

- -ings representing like parts.

My invention relates to methods for reinforcing an electrical current on a conductor by the action of said current upon another current and theimpressing or superposing upon said first mentioned current of a third,

current set up or controlled by said second current; and improved method has reference particularly but not" exclusively to the reinforcing currents.

This application is a division of my prior copending application Serial No. 293,216, filed December 26, 1905.

F or the purpose of describing the. aforesaid improved method I have in the annexed drawings indicated apparatus that may be employed.

In these drawings: Figure 1 is a diagrammatic representation of circuit connections in a telephone system with apparatus for the practise of the method. Fig. 2 is a sim1- vlar .view of telephonic apparatus with the connecting circuits differently arranged.

Referring to these drawings and particu la'rl to Fig.v 1, a represents a circuit intended or the transmission of electrical energy. In this particular instance I will-describe the same as a. telephonic circuit connectin the separatedstations A, B, which are e'ac w ,adaptedboth for the transmission and receipt of telephonic voice-created currents;

Fpr this purpose each station is provided with. the usual receiver r, transmitter t, battery b and inductionnoil 0. At each station, andas represented in Fig 1 adjacent thereto, ther is located reinforcing repeating means at R for impressing upon the line circuit current undulations proportional to those generated in the transmitting circuit of- .the station which may beintensified; in

similar-t0 that already described, and inductively related to the line through the inamount. The means herein illustrated. com.- prises a local circuit (1, the latter including of telephonic alternating a battery e and some means for varying the energy of said local orrepeating circuit, such for example, as the variable resistance medium f, located in the repeating circuit which is here conventionally shown, but

which may be of any ordinary. or usual conand impressed upon the line circuit are inductively reproduced in the coil of the electromagnet h, causing the variable resistance f to impress similar and harmonious undulations upon the local circuit 65, as will be Well understood. The undulations of the local circuit are in turn impressed upon the main circuit to reinforce the original impulses through the medium of the induction coil g.

It is to be understood that the repeating ed to receive telephone currents and reproduce therefrom currents harmonious therewith, the invention being limited neitherto the employment of 1 a variable resistandel medium nor any otherone particular agency for the purpose.

It willbe-observed that the current undulations transmitted in either direction from one station to the other are effective in cans ing intensified but harmonious undulations to be cumulatively impressed upon the line circuit. 7

In Fig. 2 I'hav'e shown an a "plication of this invention-to a system embodying widely separated stations where. it is desired to introduce one ormore repeating stations C, D,at intervals tostep up or reinforce the weakened energy line undulations rea'ching the repeating station. Each repeater stat-ion hasa local'or repeating circuit d,

85 agency employed may be any means adapt-.

duction coil 9. There is also provided a similar magnet h, adapted to be energized by the line undulations, but herein shown as directly included in the line circuit, in-

stead of inductively associated therewith as before. Y

It will be observed that the single repeating circuit at each station is in operativerelation to the line for intensifying the energy undulations transmitted from either station, this being accomplishedJoy cumulatively and harmoniously adding the undulations of the repeating circuit to those of the line, no matter in what direction transmis-' sion takes place.

This discussion of the apparatus described in said drawings and its operation clearly rocally arranged repeating instruments. In bridged arrangements while the new current set up by the repeating or reinforcing instrumentalities is theoretically added to the original line current, all line currents are divided among the different circuit portions formed by. the bridged connection in the line and consequently the full line energy does not reach the distant terminal receiving instrument although it is for the purpose of strengthening the action of such instrument that the current is reinforced. Moreover in all such bridged arrangements, with which I am familiar, artificial resistances or other elements are interposed in the circuits (that is, elements having no necessar connection with the direct current reinforcing operation) and all current effects upon the line are thereby weakened. Still further it is generally necessary with such bridged arrangements "to provide means whereby the different line portions may be adjust-ably brought into an electri cally' balanced relation as the circuit con--- nections from time to time, afieoted by the.

reinforcing station, vary the, length or electrical qualities of the difl/rent circuit portions. In closed circuit/reinforcing arrangements involving .rciprocally arranged repeating instru n entalities (that is, duplicate repeater arrangements, ea h section of the line being independent of ie other except as related through the rep ating devices and each fsection of. the ine having connected theryain the receiving 1ement of one repeater, of which the transvmitt ng element is connected into the other line section, and the transmitting element of the other repeater of which the receiving element is connected to the other line section) the action is substantially a pure relaying action similar to what takes place' in a two-way telegraphic repeater; that is, there is no cumulating of the repeatercaused currentupon the original line current; and in such forms there is in general a tendency to a strong reactive singing in the line unless at least artificial balancing or neutralizing elements are introduced into line connections.

By the use of my invention as herein disclosed provision is made for synchronously and harmoniously reinforcing a telephone line currentby means of repeater circuits serially related to the line, said repeater circuits including. appropriate receiving elements and appropriate transmitting elements magnetically independent each of the other. Both synchronous and harmoniou's action of the rep'eater circuits on the line is necessary for uniform and most successful operation.

Lackv of synchromsm results from mechanical or electromagnetic lag in repeater circuits as related to associated line circuits;-and the efiect of such lack of synchronism is to distort the form of the line current wave so that a donble-peaked Wave may result from a single peaked wave originally impressed upon the had, thus pro ducing self-continuing or reactive operation of the whole circuit arrangement. This is the characteristic fault of such arrangements as shown in the patent to Gilliland, #24t7,631, September 27, 1881, and similar arrangements;-andis present in bridged forms of repeater circuits such as are shown in patents to Arnold, #542,618 and 542,619, and analogous arrangements. Reaction in such forms results from mechanical and electromagnetic lalg factors between the excitation of the repeating instrumentalities by the line and the resulting excitation of the line by the repeating instrumentalities, with subsequent renewed excitation of the repeater. It is analogous to the reaction produced by holding a commercial telephone receiver closely opposite a related transmitter in which relation frequently a continuous reactive singing of the receiver is heard. This is roduced by the lag in the passage through tiie air of the vibration set up by the receiver diaphragm, which vibration is rimarily caused by the original moveme t of the transmitter diaphragm.

The elyfctric impulse flows at the assigned speed cf electric current conductor flow but he air wave moves at a relatively slow speed" so that each receiver diaphragm more meat causes a subsequent movement of the transmitter diaphragm. Where a telephone receiver and transmitter are operatively connected or related electrically each to the other as in closedrepeater circuits the conditions of lag causing reaction are closely analogous to those ust discussed.

By harmonious action of the repeater circuits and instrumentalities on the line,

as distinguished from synchronous action, I have reference to two factors. The

first is the relation of the Wave form received by the-repeater circuits from the line and the Waveform re-impressed on the latter by the former. These obviously'should be the same ;Which means, when alternat; ing line currents are employed, that the same phase (positive or negative) received by the repeatercircuits from the line should be rerimpressed *by them on the line. I This it will be apparent (disregarding internal connections in the repeater circuits, that is, connections therein other than those to the main line) is accomplished by properly arranging the terminal connections of the repeater circuits 'to the line. Each set of repeater circuits should be so connected to the line that the line wave form impressed on the repeater-receiver shall be re-impressed by the repeater-transmitter on the line; If this is not done, obviouslyadistortionjand change of Wave form on the line will or may result, with consequent double-peaked Wave forms in place of single-peaked Wave forms; and, since the line and the repeater instrumentalities are in electrical connection, selfexcitation or reaction will be produced, with a singing of the line. This is a characteristic fault of bridged forms of repeater circuits, and results therein from the fact that the various portions of the cir' cuit formed by the bridge necessarily have, under varying operating conditions and. unless means are provided for artificially balancing the same, various and different components of resistance, capacity and inductance, which produce change of the Wave form as originally impressed on the line.

The serial connection herein disclosed avoids these factors because the unitary condition of the transmitting line is not disturbed. A second factor relating to harmonious circuiting has to do with the internal connection in the repeater circuits. Assuming as constituent elements of the repeating instrumentalities an initially magnetized receiving element, responding differentially to the Y phases of an alternating current (constituting therefore, as does the commercial receiver when used With alternating currents, a true polarized device) and a local direct current varied in value by such receiving device and in turn operating to vary or produce a line current that finally reacts on the repeater-receiver, it is importantthat the connection of the circuit carrying the 1 local current to the repeater-receiver governed current-varylng means afi'ect lng such impression put on the line by the repeater will produce in the said local current the change necessary to produce said last mentioned -current impression. clear, if the repeater local-current varying: device is a variable resistance microphone acted upon by an armature in the field of an initially magnetized electro-magnet adapted to be energized by the main. line, then not only must the terminal connections of the line and ,the repeater circuit-s be ha-rmonious, but the connections of the local circuit to said current-varying device must be such that any given direction of movement of the said armature shall produce an immediate local direct-current effect (and consequent. line current effect) that, ultimately, reacting on the said magnet through the'line, Will produce the same direction of movement of said armature. If this is not .local current shall be such that any current To make this done a-condition is produced analogous to 7 that existing in the interrupter of induction coils; that is, each change of movement by the armature tends, through the connections and magnetic arrangement, to produce an opposite movement thereof, and reactive singing 'of the line will result. a It Will be evident from the foregoing that in the serially connected repeater or reinforcing circuits and instrumentalities that I have disclosed I have provided means Whereby a transmitter line may be kept in the normal, unitary connection from terminal to terminal and telephone currents thereon reinforced by harmonious connection and synchronous action, so that the disturbing and variable factors present in bridged or reciprocally arranged repeaters are avoided. The action of the line on the repeater and of the repeater on the line is obviously best had through undivided circuits. I do not herein claim the apparatus for carrying out the described method, such apparatus being claimed in another copending application.

Where in the claims I refer to the repeater-receiver element and the repeatertransmitter element as being magnetically independent each of the other What I mean is'such construction that the coils or Windings of one do not act upon the coils or Windings of the other in any except the desired manner, so that they are free from opera tive interference. This in general means (since the coils necessarily have magnetlc cores) that the magnetic cores of the respective elements are separate from each other, whereby the magnetic flux set up-by the receiving instrument is not directly operative upon the transmitting element, the latter being designed to be controlled by an independently created magnetic flux.

Claims:

l. The method ofreinforcing a varying current which consists in setting up by the series act-ion of a conductor carrying said current variations of a second current barmonious with the variations of said first mentioned current; in creating by the action of said second current a third varying current harmonious in its variations with the variations of said second current; and in impressing said third mentioned current serially upon said. first mentioned current synchronously and harmoniously with the variations thereof; and which consists further in maintaining the said action of said first mentioned varying current on said second current and the said action of said third mentioned current on said first mentioned current each magnetically independent of.

the other.

2. The method of reinforcing an alternating current which consists in setting up by the series act-ion of a conductor carrying said current variations of a second current harmonious with the variations of said first mentioned current; in creating by the action of said second current a third varying current harmonious in its variations With the variations of said second current; and in impressing said third mentioned current ,rially upon said first mentioned current syn chronously and harmoniously with the variations thereof; and which consists further in maintaining the said action of said first mentioned varying current on said second current and the said action of said third mentioned current on said first mentioned current each magnetically independent oi: the other.

3. The method of reinforcing alternating telephone currents on aline which consists in of current fiow' in said line an undulatory direct current harmonious with the/waveform of said alternating current; in setting up by the undulations of said direct current a second alternating current, and in impressing said second alternating current on said line by series action thereon synchronously and harmoniously with said first mentioned alternating current; and ,which consists further in maintaining said two series actions magnetically independent of each other.

4. The method of reinforcing alternating telephone currents on a line which consists in setting up by the series action of said line a second alternating current harmonious in its wave form with said first mentioned alternating current; and in impressing said second alternating current on said line by series action thereon synchronously and harmoniously with said first mentioned al- "ternating current; and which consists further in maintaining said two series actions magnetically independent of each other.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses.

Witnesses E mnn'r'r S. EMERY,

Roxanna. H. K AMMLER Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents,

' Washington, D. 0.

settingup by the series action of variations. 

